Firma Automatyka-Pomiary-Sterowanie S.A. (APS S.A.) modernizated a 0.4 kV switchgear and the works also included coal handling equipment powered by this switchgear for ENERGA Power Plans in Ostrołęka.
The works were carried out on the basis of Employer's design and their scope included, among others:
- delivery, installation and commissioning of 0.4 kV two-section switchgear double type NGW R with rail bridges with rated current In = 2500A and SZR layout type AZRS-3;
- dismantling of existing transformers TWA and TWB 800 kVA and supply, installation commissioning of 2 new transformers 1600kVA;
- temporary supply of container switchboard, switching and running power and control circuits powered from the exchanged switchboard;
- supply and installation of equipment and start-up of two fields in 6kV switchgear. Fields were equipped with new circuit breakers type HVX-12-31-06, current transformers GIS and field controller megaMUZ-2;
- general construction work performed in the switching station building along with the adaptation of the switching transformer chambers to meet the needs of new transformers;
- installation of lighting and repair outlets in the switching station building;
- delivery, installation and commissioning of equipment on twelve carburizing conveyor belts in the plant;
- delivery, installation and commissioning of inverter systems type ACS800 for drives with capacities up to 30kW and 55kW;
- connection of the NGW R switchgeat to the control and supervision system EControl;
- installation of fire protection system including switchgears and transformer chambers;
- prefabrication of automation cabinets, assembly on site and inclusion to the control and supervision system over the work of coal handling system;
- execution of process graphic in the system InTouch 10.0;
- configuration and software of redundant RX3i GE Fanuc controllers;
- conduct of performance tests, measurements, technical start-up and participation in a test run of the upgraded coal handling system;
- staff training;
- preparation of as-built documentation.
All the work was carried out on the equipment in service. For this reason, in order to ensure continuity of supply during the construction works in the switching station building, all power and control circuits were moved to a temporary container cabinet. The switchgear was made on the basis of the design prepared by APS S.A.
Power fields and coupling field of new 0.4 kV switchgears are equipped with aAir circuit breakers ABB SACE EMAX and PECA network analyzers.The device used AZRS-3 was used as Automatic Transfer Switching Equipment. In addition, all outgoing bays feeding the motor drives are equipped with digital engine LV safeguards miniMUZ-SR.
Such equipment of switchboards allow for preview in the master system ECONTROL parameters of their operation and for remote switches. In order to make this possible in the 0.4 kV switchgear building was installed the cabinet with separatorsI I/ O, local
system controller and communication modules. The combination with the system cabinet located near the control room was carried out by optical fiber cable.
The power supply of 0.4 kV switchgears was also completely modernized. In addition to replacing the oil transformers to new resin transformers 6/0, 4 kV equipped with a temperature control system RTT-8, were upgraded the transformer fields in 6kV switching station. Fields were equipped with new circuit breakers Schneider Electric type HVX-12-31-06, current transformers GiS12d, ground fault transformer IO-22E, field driver MegaMUZ-2.
In terms of instrumentation, for the purpose of traffic control of the carburizing system, belt conveyors were equipped with new cable pull switches, belt motion sensors, transfer station sensors, misalignment sensors, new warning sirens, local control cabinets. The former, manual way of setting the T15 hopper was modernized in such a way that the control system was equipped with a programmable ultrasonic distance sensor Senix ToughSonic with analog output 4-20mA. This solution allows to adjust the position of the hopper in the set position from the host system. All equipment was made in explosion-proof version.
In a normal operating system carburizing conveyor systems operate in the regime of full automation and can be used by the operator from the control room using the master control and supervision system. For maintenance purposes it is possible to control from local cabinets.
Control and carburizing process visualization system was based on controllers GE Fanuc PACSystems RX3i and Wonderware InTouch software. Figure 3 presents the main synoptic mask depicting thepiece of carburizing system modernized by APS S.A . Each device remotely controlled by an operator has control ignition, which shows the current status of drives and diagnostics of all sensors attached to the device. For maintenance purposes it is possible to control the local cabinets located near the belt conveyor drives. The operator sets the carburizing process that supports the transmission route of fuel by setting the distribution devices (chutes, hopper, trolley conveyor). Then the controller recognizes the set alternative route, selects the appropriate device for activation sequence and shows readiness of selected drives on the operator station. After approval by the operator of the equipment they are activated with the use of all necessary locks and safeguards. The driver includes several variants of the fuel transfer which fully covers the needs of the investor.
By using a dual power supply with backup power, redundant communication between the controllers and the remote systems I/O, optic ring fiber for communication of controllers and operator stations and redundant CPUs, the carburizing process gained a new quality and extremely high reliability.
